Chess960, also known as Fischer Random Chess<!-- Please do not add trademarks and brand names that are meet WP:COMMONNAME here, they are listed below. -->, is a chess variant that randomizes the starting position of the pieces on the back rank. It was introduced by former world chess champion Bobby Fischer in 1996 to reduce the emphasis on opening preparation and to encourage creativity in play. Chess960 uses the same board and pieces as classical chess, but the starting position of the pieces on the players' is randomized, following certain rules. The random setup makes gaining an advantage through the memorization of openings unfeasible. Players instead must rely on their skill and creativity.
Randomizing the main pieces had long been known as shuffle chess, but Fischer introduced new rules for the initial random setup, "preserving the dynamic nature of the game by retaining for each player and the right to castle for both sides". The result is 960 distinct possible starting positions.
In 2008, FIDE added Chess960 to an appendix of the Laws of Chess.